13C solid-state NMR spectra of a crystalline griseofulvin, b melt-quenched amorphous griseofulvin, c hydroxypropylmethylcellulose acetate succinate (HPMCAS), d spray-dried dispersion containing 20% griseofulvin and 80% HPMCAS, e centrifugal evaporated dispersion containing 20% griseofulvin and 80% HPMCAS, f lyophilized dispersion containing 20% griseofulvin and 80% HPMCAS